ArticleVeterinary world2025
Genomic and evolutionary characterization of newly emerged highly pathogenic avian influenza H5N1 clade (2023-2025).
Article in Veterinary world, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5 papers.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
5 citing papers in PubMed.
- Article
- First report of molecular genotyping, pathotyping, and histopathological characterization of lentogenic genotype II Newcastle disease virus circulating in young ostrich flocks in Egypt.Veterinary world · 2026Article
- Full genome sequencing, evolutionary dynamics, and pathogenicity evaluation of chicken infectious anemia virus with emphasis on Upper Egypt reveals genetic variability linked to vaccinal strains.Virology journal · 2026Article
- Histopathological diagnosis and genetic diversity of avian encephalomyelitis virus circulating in broiler farms in Egypt.Open veterinary journal · 2026Article
- Converging infectious disease threats in the post-COVID era: surveillance fragility, pandemic risk, and global preparedness.Frontiers in public health · 2026Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Background and Aim: Highly pathogenic avian influenza virus (HPAI) H5N1 continues to threaten poultry biosecurity worldwide due to rapid antigenic drift and reassortment. Since late 2020, clade 2.3.4.4b strains have dominated outbreaks across multiple continents. This study genetically characterized H5N1 isolates circulating in Upper Egypt during 2023-2025, clarified their phylogenetic origin, and compared them with vaccine strains used nationally. Materials and Methods: A total of 100 samples from 25 broiler flocks showing respiratory and neurological symptoms across New Valley, Assiut, and El-Minya governorates were examined. Specimens were screened for avian influenza subtypes (H5N1, H9N2, H5N8, H6N2) and differential viral pathogens (Newcastle disease virus, infectious bronchitis virus, infectious laryngotracheitis virus, infectious bursal disease virus) using reverse-transcription quantitative polymerase chain reaction (RT-qPCR). Positive isolates were propagated in specific-pathogen-free embryonated chicken eggs and identified through hemagglutination and hemagglutination inhibition assays. Partial hemagglutinin gene sequencing and phylogenetic analyses were performed using Molecular Evolutionary Genetics Analysis version 7.0. Results: HPAI-H5N1 was detected in 16% (4/25) of flocks, showing 25%-50% mortality. Five isolates displayed high hemagglutination titers (7-8 log2) and were confirmed as H5N1 subtype by RT-qPCR. Phylogenetic analysis classified New Valley-1-H5N1-2023 and New Valley-2-H5N1-2024 within clade 2.3.4.4b. These strains shared 96%-99% nucleotide and amino acid identity with recent Egyptian and Eurasian H5N1 isolates but only 72%-84% with currently used Egyptian vaccine seeds (e.g., MEFLUVAC [Kemin Industries, Inc., USA], EgyFlu [Nagy Awad Group, Cairo, Egypt]). Mutations R72S, A83D, and T140A were identified in receptor-binding and antigenic regions of hemagglutination, implying potential antigenic drift. Conclusion: This is the first documentation of clade 2.3.4.4b HPAI-H5N1 circulation in broiler flocks of Upper Egypt. The low genetic relatedness to existing vaccine strains indicates probable vaccine mismatch and reduced protection. Continuous molecular surveillance, integration of full-genome sequencing, and periodic vaccine seed updates are essential for effective containment. Enhanced monitoring at the domestic-wild bird interface will help mitigate cross-species transmission and align with One Health strategies for zoonotic risk reduction.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.